"The leaders have agreed on a way forward," said Jim Manley, a spokesman for Senate Majority Leader Harry Reid, D-Nev.

The measure, sidetracked a week ago, is expected to return to the Senate floor for additional debate as early as next week.

The legislation has generated intense controversy, particularly for provisions envisioning eventual citizenship for many of the estimated 12 million immigrants now in the country unlawfully. The bill also calls for greater border security and a crackdown on the hiring of illegal employees.

No guarantee of passageThe decision to revive the measure does not necessarily portend passage in the Senate. Critics of the measure have denounced it as conferring amnesty on millions of lawbreakers, and it remains unclear how strenuously they will attempt to prevent its approval.

The decision to bring the bill back for more debate was made at a meeting involving Reid, Sen. Mitch McConnell of Kentucky, the Republican leader, and key supporters of the legislation.

McConnell left the closed-door meeting without speaking with reporters.

But several officials said the decision had been made to make one additional stab at passing the measure, which is Bush's top domestic priority.

Bush was overseas the first few days after the bill was sidetracked last week, but he returned Monday night and immediately plunged into the rescue effort. He met with Republican senators in the Capitol on Tuesday, and on Thursday said he would support a call for $4.4 billion in immediate funding aimed at "securing our borders and enforcing our laws at the work site."

Precise details of the rescue plan were not immediately disclosed.

In general, according to officials familiar with the discussions, the bill's supporters had recommended giving both Republicans and Democrats roughly a dozen chances each to amend the measure, with the hope that they would then combine to provide the 60 votes needed to overcome a filibuster by die-hard opponents.

Officials also said the Bush-backed plan for accelerated funding would be among the changes to be voted on. So, too, a proposal by Sen. Kay Bailey Hutchison, R-Texas, to toughen a requirement for illegal immigrants to return to their home country before gaining legal status.

But in a gauge of the complexity of the rescue effort, officials said the Senate's decision last week to terminate a temporary-worker program after five years would likely not be subject to change before a vote on final passage. Many of the bill's strongest supporters opposed the five-year provision when it came to a vote last week.

The officials who described the emerging plan did so on condition of anonymity, saying the negotiations had been conducted in private.

"We're going to show the American people that the promises in this bill will be kept," Bush said, two days after launching a personal rescue mission.

Any agreement is subject to approval by Reid, who has said repeatedly it is up to Bush and Republicans to line up the votes needed to advance the measure if it is to be brought back to the Senate for debate. Reid, who has expressed misgivings about elements of the bill, sidetracked it last week after supporters gained only 45 of the 60 votes needed.

Republicans accounted for only seven of the 45 votes, and Reid said earlier this week, "We'll move on to immigration when they have their own act together."

Bush's decision to personally announce support for the accelerated funding reflected concerns expressed by Republican senators at a closed-door meeting on Tuesday. Several told him their constituents doubted the government was capable of following through on a commitment to enforce immigration laws.

In a letter sent to Bush before the meeting, Georgia Republican Sens. Saxby Chambliss and Johnny Isakson wrote, "This lack of trust is rooted in the mistakes made in 1986, and the continued chaos surrounding our immigration laws. Understandably, the lack of credibility the federal government has on this issue gives merit to the skepticism of many about future immigration reform."

Under the legislation as drafted, money for border enforcement would be collected gradually as illegal immigrants pay the fines and fees needed to achieve legal status. The letter asked Bush to secure the border before other elements of the immigration measure go into effect, and the president agreed in his remarks to the Associated Builders and Contractors.

"One common concern is whether the government will provide the resources to meet the goals in the bill. They say, 'It's fine to talk about it, are you actually going to do something?'" he said.

"To answer these concerns I support an amendment that will provide $4.4 billion in immediate additional funding for securing our borders and enforcing our laws at the work site," he said.

"By matching our benchmarks with these critical funds, we're going to show the American people that the promises in this bill will be kept."

Two Republican supporters of the legislation, Sens. Lindsey Graham of South Carolina and Jon Kyl of Arizona, had previously proposed advanced funding.

"The moment the presidential signing pen meets the paper these funds will be available," Graham said in a statement welcoming Bush's remarks.

But Sen. Jim DeMint, R-S.C., who opposes the legislation, took a different view. "I appreciate the effort to fund border security, but there's simply no reason why we should be forced to tie amnesty to it. If the administration was serious about fulfilling the border security promises, then this funding should have been supported all along, not offered at the last minute to attract votes to a bad bill."